Direct motor-drive portable angle grinder

ABSTRACT

The present invention is an original direct motor-drive portable angle grinder with a disc type motor installed in a position adjacent to the grinding wheel and an outer motor rotating part coaxially and directly driving the grinding wheel. By means of the direct drive, the present invention prevents the emission of noise made by angle type transmission devices. Moreover, an inertial body is installed on the rotating housing that is integrated with the rotating part to form a flywheel or the rotating housing and the inertial body are integrated into a single reinforced structure to enable a flywheel function in order to improve the grinding, polishing and machining or cutting abilities of the grinding wheel.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No. 12/458,479, filed on Jul. 14, 2009, which is incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a direct motor-drive portable angle grinder with a disc type motor installed in a position adjacent to the grinding wheel and an outer motor rotating part coaxially and directly driving the grinding wheel. By means of the direct drive, the present invention prevents the emission of noise made by angle type transmission devices. Moreover, an inertial body is installed on the rotating housing that is integrated with the rotating part to form a flywheel or the rotating housing and the inertial body are integrated into a single reinforced structure to enable a flywheel function in order to improve the grinding, polishing and machining or cutting abilities of the grinding wheel. Aside from a manually controlled electromechanical device, a power storing and discharging device is also installed in the handle for use as a power source.

(b) Description of the Prior Art

Traditional motor-driven right-angle type portable grinder is an electrical tool designed according to ergonomics. Its structural features are the following:

(1) The angular difference between the handle axis extending from the housing and the grinding wheel axis is between 30° and 150°;

(2) The electric motor is installed in the handle;

(3) An angle type transmission device such as a bevel gear set is present in between the grinding wheel spindle and the handle motor spindle;

Because the above structure necessitates an angle type transmission device; hence its deficiency is its very loud noise.

SUMMARY OF THE INVENTION

The present invention is an original direct motor-drive portable angle grinder with a disc type motor installed in a position adjacent to the grinding wheel and an outer motor rotating part coaxially and directly driving the grinding wheel. By means of the direct drive, the present invention prevents the emission of noise made by angle type transmission devices. Moreover, an inertial body is installed on the rotating housing that is integrated with the rotating part to form a flywheel or the rotating housing and the inertial body are integrated into a single reinforced structure to enable a flywheel function in order to improve the grinding, polishing and machining or cutting abilities of the grinding wheel. Aside from a manually controlled electromechanical device, a power storing and discharging device is also installed in the handle for use as a power source.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural drawing showing the main components of the direct motor-drive portable angle grinder of the present invention

FIG. 2 is the first operational diagram of the present invention showing the drive motor rotating part and housing coaxially driving the grinding wheel

FIG. 3 is the second operational diagram of the present invention

FIG. 4 is the third operational diagram of the present invention

FIG. 5 is the fourth operational diagram of the present invention

FIG. 6 is the operational view of the present invention showing the additional installation of an inertial flywheel in FIG. 2

FIG. 7 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 3

FIG. 8 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 4

FIG. 9 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 5

FIG. 10 is the first operational diagram of the commutator-type motor formed together by the housing and the internal rotation type motor of the present invention

FIG. 11 is the second operational diagram of the commutator-type motor formed together by the housing and the internal rotation type motor of the present invention

FIG. 12 is the first operational diagram of the structure formed together by the housing and the internal rotation type brushless motor of the present invention

FIG. 13 is the second operational diagram of the structure formed together by the housing and the internal rotation type brushless motor

DESCRIPTION OF MAIN COMPONENT SYMBOLS

-   (100): Drive motor -   (150): Commutator-type drive motor -   (151): Commutator-type drive motor static part -   (152): Commutator-type drive motor rotating part -   (153): Commutator -   (154): Brush assembly -   (160): Brushless motor -   (161): Brushless motor static part -   (162): Brushless motor rotating part -   (200): Motor rotating part -   (201): Rotating housing -   (202): Commutator type motor magnetic field structure -   (205): Motor static part -   (206): Motor winding -   (210): Fin structure -   (250): Vent -   (300): Motor spindle -   (400): Housing -   (500): Handle -   (600): Electric brush -   (700): Insulation -   (800): Grinding wheel -   (900): Blades -   (1000): Inertial body -   (1100): Guard -   (1200): Power storing and discharging device -   (1300): Control circuit -   (1400): Manually operated electromechanical device -   (1500): Power cord

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is an original direct motor-drive portable angle grinder with a disc type motor installed in a position adjacent to the grinding wheel and an outer motor rotating part coaxially and directly driving the grinding wheel or the circular saw. By means of the direct drive, the present invention prevents the emission of noise made by angle type transmission devices. Moreover, an inertial body is installed on the rotating housing that is integrated with the rotating part to form a flywheel or the rotating housing and the inertial body are integrated into a single reinforced structure to enable a flywheel function in order to improve the grinding, polishing and machining or cutting abilities of the grinding wheel or the circular saw. Aside from a manually controlled electromechanical device, a power storing and discharging device is also installed in the handle for use as a power source. FIG. 1 is a structural drawing showing the main components of the present invention. The structural pattern of the outer rotating motor direct drive portable angle grinder in FIG. 1 is formed by the coaxial drive of the outer rotating part of the drive motor and the housing on the grinding wheel. The main components include:

-   -   Drive motor (100): Consists of alternating or direct current,         brush or brushless, synchronous or asynchronous of outer         rotating electric motor, including cylindrical, conical or disc         type motor static and motor rotating parts (200) that are,         directly or indirectly through the insulation (700), integrated         with the rotating housing (201) of the motor to enable the outer         rotating motor part to make high speed and high inertial rotary         drive to facilitate grinding, polishing and cutting of         workpieces of the grinding wheel (800) or the circular saw and         heat dissipation. The grinding wheel (800) is coaxially         installed with the spindle (300) of the motor rotating part         (200).     -   Housing (400): A structure formed by solid state material for         the installation of the drive motor (100) and a handle (500)         formed by an extended body or assembly. Its features are the         drive motor (100) is installed in the housing (400); the         deflection angle between the axis of the spindle (300) of the         drive motor (100) of the rotating part (200) and the axis of the         handle (500) is between 30°-150°.     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200), and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct motor-drive portable angle         grinder.     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct motor-drive         portable angle grinder; and formed by electromechanical or solid         state electronic structures for turning the motor on or off,         and/or changing the rotational speed and/or varying the speed.     -   Control circuit (1300): Provide operational capability for the         execution of turning the motor on and off and/or changing the         rotational speed and/or varying the speed; and/or for the         control and protection of voltage and current.     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (200) to provide rotary drive operation for         grinding, polishing and cutting workpieces.     -   Guard (1100): installed on one side of the grinding wheel (800)         and the rotating part (200) adjacent to the handle.

The following operational diagrams of the direct motor-drive portable angle grinder in FIG. 1 are drawn according to the choices of motors used which include:

FIG. 2 is the first operational diagram of the present invention;

FIG. 3 is the second operational diagram of the present invention;

FIG. 4 is the third operational diagram of the present invention;

FIG. 5 is the fourth operational diagram of the present invention;

FIG. 2 is the first operational diagram of the present invention showing the motor rotating part and housing coaxially driving the grinding wheel. The operational electric motor is of the brushless type using city mains as its power source. The main components include:

-   -   Drive motor (100): Consists of alternating or direct current,         brushless of synchronous or asynchronous outer rotating electric         motor, including cylindrical, conical or disc type motor static         and motor rotating parts (200) that are, directly or indirectly         through the insulation (700), integrated with the rotating         housing (201) of the motor to enable the outer motor rotating         part to make high speed and high inertial rotary drive to         facilitate grinding, polishing and cutting of workpieces of the         grinding wheel (800) or the circular saw and heat dissipation.         The grinding wheel (800) is coaxially installed with the spindle         (300) of the motor rotating part (200).     -   Housing (400): A structure formed by solid state material for         the installation of the drive motor (100) and a handle (500)         formed by an extended body or assembly. Its features are the         drive motor (100) is installed in the housing (400); the         deflection angle between the axis of the spindle (300) of the         drive motor (100) of the rotating part (200) and the axis of the         handle (500) is between 30°-150°.     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200), and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct motor-drive portable angle         grinder.     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct motor-drive         portable angle grinder; and formed by electromechanical or solid         state electronic structures for turning the motor on or off,         and/or changing the rotational speed and/or varying the speed.     -   Control circuit (1300): Provide operational capability for the         execution of turning the motor on and off and/or changing the         rotational speed and/or varying the speed; and/or for the         control and protection of voltage and current.     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (200) to provide rotary drive operation for         grinding, polishing and cutting workpieces.     -   Guard (1100): installed on one side of the grinding wheel (800)         and the rotating part (200) adjacent to the handle

Thereinto: The motor rotating part (200) is snugly installed inside the driven rotating housing (201) to enable the outer motor rotating part to make high speed and high inertial rotary drive in order to facilitate grinding, polishing and cutting operations of the grinder and for heat dissipation of motor. The grinding wheel (800) is coaxially installed on the spindle (300) of the motor rotating part (200). The motor winding (206) is installed on the motor static part (205) through the insulation (700).

FIG. 3 is the second operational diagram of the present invention showing the deployment of commutator type outer motor as the driving motor in FIG. 1. The motor rotating part (200) is consisted of an armature with electric energy supplied through the electric brush (600).

The main components are:

-   -   Drive motor (100): Consists of alternating or direct current,         commutator type brush of outer rotating electric motor,         including cylindrical, conical or disc type permanent magnet or         coil-wound type field-exciting commutator type motor magnetic         field structure (202) and armature-formed motor rotating part         (200) with power supplied by the electric brush (600). Directly         or through the insulation (700), the motor rotating part (200)         is integrated with the rotating housing (201) of the motor to         enable the outer motor rotating part to make high speed and high         inertial rotary drive to facilitate grinding, polishing and         cutting of workpieces of the grinding wheel (800) or the         circular saw and heat dissipation. The grinding wheel (800) is         coaxially installed on the spindle (300) of the motor rotating         part (200).     -   Housing (400): A structure formed by solid state material for         the installation of the drive motor (100) and a handle (500)         formed by an extended body or assembly. Its features are the         drive motor (100) is installed in the housing (400); the         deflection angle between the axis of the spindle (300) of the         drive motor (100) of the rotating part (200) and the axis of the         handle (500) is between 30°-150 °.     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400) and optional         devices like control circuit (1300), or indicator lamp, and         display devices for the operational control of the direct         motor-drive portable angle grinder.     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct motor-drive         portable angle grinder; and formed by electromechanical or solid         state electronic structures for turning the motor on or off,         and/or changing the rotational speed and/or varying the speed.     -   Control circuit (1300): Provide operational capability for the         execution of turning the motor on and off and/or changing the         rotational speed and/or varying the speed; and/or for the         control and protection of voltage and current.     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (200) to provide rotary drive operation for         grinding, polishing and cutting workpieces.     -   Guard (1100): installed on one side of the grinding wheel (800)         and the rotating part (200) adjacent to the handle

Thereinto: The motor rotating part (200) is snugly installed inside the driven rotating housing (201) directly or through the insulation 700 to enable the outer motor rotating part to make high speed and high inertial rotary drive in order to facilitate grinding, polishing and cutting operations of the grinder and for heat dissipation of motor. The grinding wheel (800) is coaxially installed with the spindle (300) of the motor rotating part (200).

FIG. 4 is the third operational diagram of the present invention showing the installation of the power storing and discharging device (1200) and the manually operated electromechanical device (1400) in the handle (500) in FIG. 2.

The main components include:

-   -   Drive motor (100): Consists of alternating or direct current,         brushless of synchronous or asynchronous outer rotating electric         motor, including cylindrical, conical or disc type motor static         and motor rotating parts (200). Directly or through the         insulation (700), the motor rotating part (200) is integrated         with the rotating housing (201) of the motor to enable the outer         motor rotating part to make high speed and high inertial rotary         drive to facilitate grinding, polishing and cutting of         workpieces of the grinding wheel (800) or the circular saw and         heat dissipation. The grinding wheel (800) is coaxially         installed with the spindle (300) of the motor rotating part         (200).     -   Housing (400): A structure formed by solid state material for         the installation of the drive motor (100) and a handle (500)         formed by an extended body or assembly. Its features are the         drive motor (100) is installed in the housing (400); the         deflection angle between the axis of the spindle (300) of the         drive motor (100) of the rotating part (200) and the axis of the         handle (500) is between 30°-150 °.     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct motor-drive portable angle         grinder.     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct motor-drive         portable angle grinder; and formed by electromechanical or solid         state electronic structures for turning the motor on or off,         and/or changing the rotational speed and/or varying the speed.     -   Control circuit (1300): Provide operational capability for the         execution of turning the motor on and off and/or changing the         rotational speed and/or varying the speed; and/or for the         control and protection of voltage and current.     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (200) to provide rotary drive operation for         grinding, polishing and cutting workpieces.     -   Guard (1100): installed on one side of the grinding wheel (800)         and the rotating part (200) adjacent to the handle

Thereinto: The motor rotating part (200) is snugly installed inside the driven rotating housing (201) to enable the outer motor rotating part to make high speed and high inertial rotary drive in order to facilitate grinding, polishing and cutting operations of the grinder and for heat dissipation of motor. The grinding wheel (800) is coaxially installed with the spindle (300) of the motor rotating part (200).

FIG. 5 is the fourth operational diagram of the present invention showing the installation of the power storing and discharging device (1200) and the manually operated electromechanical device (1400) in the handle (500) in FIG. 3.

The main components are:

-   -   Drive motor (100): Consists of alternating or direct current         commutator type brush of outer rotating electric motor,         including cylindrical, conical or disc type permanent magnet or         coil-wound type field-exciting commutator type motor magnetic         field structure (202) and the motor rotating part (200).         Directly or through the insulation (700), the motor rotating         part (200) is integrated with the rotating housing (201) of the         motor to enable the outer motor rotating part to make high speed         and high inertial rotary drive to facilitate grinding, polishing         and cutting of workpieces of the grinding wheel (800) or the         circular saw and heat dissipation. The grinding wheel (800) is         coaxially installed on the spindle (300) of the motor rotating         part (200).     -   Housing (400): A structure formed by solid state material for         the installation of the drive motor (100) and a handle (500)         formed by an extended body or assembly. Its features are the         drive motor (100) is installed in the housing (400); the         deflection angle between the axis of the spindle (300) of the         drive motor (100) of the rotating part (200) and the axis of the         handle (500) is between 30°-150°.     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct motor-drive portable angle         grinder.     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct motor-drive         portable angle grinder; and formed by electromechanical or solid         state electronic structures for turning the motor on or off,         and/or changing the rotational speed and/or varying the speed.     -   Control circuit (1300): Provide operational capability for the         execution of turning the motor on and off and/or changing the         rotational speed and/or varying the speed; and/or for the         control and protection of voltage and current.     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (200) to provide rotary drive operation for         grinding, polishing and cutting workpieces.     -   Guard (1100): installed on one side of the grinding wheel (800)         and the rotating part (200) adjacent to the handle.

The grinding, polishing or cutting abilities of the grinder are improved by the present invention of a direct motor-drive portable angle grinder. Furthermore, an additional drive motor (100) is installed on the housing driven by the motor rotating part (200) or the motor rotating part (200) and the drive motor (100) are made into one integrated body in order to increase the inertial mass.

FIG. 6 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 2.

Aside from showing the structures in FIG. 2, FIG. 6 also shows the installation of a inertial body (1000) around the motor rotating part (200) and the grinding wheel (800) that enables the high inertial mass outer motor rotating part to make high speed and high inertia rotary drive in order to facilitate the workpiece grinding, polishing or cutting operations of the grinder and dissipating heat of the motor. The spindle (300) of the motor rotating part (200) is coaxially installed with the grinding wheel (800).

FIG. 7 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 3.

Aside from showing the structures in FIG. 3, FIG. 7 also shows the installation of a inertial body (1000) around the motor rotating part (200) and the grinding wheel (800) that enables the high inertial mass outer motor rotating part to make high speed and high inertia rotary drive in order to facilitate the workpiece grinding, polishing or cutting operations of the grinding wheel (800) or the circular saw and dissipating heat of the motor. The spindle (300) of the motor rotating part (200) is coaxially installed with the grinding wheel (800).

FIG. 8 is the operational diagram of the present invention showing the additional installation of an inertial flywheel in FIG. 4.

Aside from showing the structures in FIG. 4, FIG. 8 also shows the installation of a inertial body (1000) around the motor rotating part (200) and the grinding wheel (800) that enables the high inertial mass outer motor rotating part to make high speed and high inertia rotary drive in order to facilitate the workpiece grinding, polishing or cutting operations of the grinding wheel (800) or the circular saw and dissipating heat of the motor. The spindle (300) of the motor rotating part (200) is coaxially installed with the grinding wheel (800).

FIG. 9 is the operational diagram of the present invention showing the additional installation of an inertial body in FIG. 5.

Aside from showing the structures in FIG. 5, FIG. 9 also shows the installation of a inertial body (1000) around the motor rotating part (200) and the grinding wheel (800) that enables the high inertial mass outer motor rotating part to make high speed and high inertia rotary drive in order to facilitate the workpiece grinding, polishing or cutting operations of the grinding wheel (800) or the circular saw and dissipating heat of the motor. The spindle (300) of the motor rotating part (200) is coaxially installed with the grinding wheel (800).

The outer motor rotating housing (201) and the inertial body (1000) of the present invention of a direct motor-drive portable angle grinder are further made into a fin structure (210) in order to improve heat dissipation during rotation.

Furthermore, the present invention is formed by internal rotation type flat, disc or relatively short cylindrical alternating current or direct current commutator-type motors. The internal rotation type flat, disc or relatively short cylindrical electric motors are for reducing workspace disruption, and to give the drive motor a better heat dissipation environment;

Its structural mode is the following:

As shown in the first operational diagram of the commutator-type motor formed together by the housing and the internal rotation type motor of the present invention in FIG. 10;

The main components are the following:

-   -   Commutator-type drive motor (150): Formed by alternating current         or direct current commutator-type drive motor (150) in flat,         disc or relatively short cylindrical forms including motor         rotating part (152) with static part (151) and commutator (153),         and brush assembly (154); wherein the static part (151) and the         spindle (300) of the motor rotating part (152) and one end of         the bearing are directly installed on the housing (400); the         other externally exposed end of the spindle (300) of the         rotating part (152) of the internal rotation commutator-type         drive motor (150) is for coaxial installation of the grinding         wheel (800) or the circular saw for workpiece polishing,         grinding and cutting operations of the grinding wheel (800) or         the circular saw which are driven by the internal rotation type         motor rotating part (152);     -   Housing (400): A structure formed by solid state material for         the installation of the commutator-type drive motor (150) and a         handle (500) formed by an extended body or assembly. The static         part (151) and the spindle (300) of the rotating part (152) of         the commutator-type drive motor (150) and one end of the bearing         combine with the housing (400). The deflection angle between the         axis of the spindle (300) of the rotating part (152) of the         commutator-type drive motor (150) and the axis of the handle         (500) is between 30°-150°;     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct commutator-type drive motor         (150)-driven portable angle grinder;     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct commutator-type         drive motor (150)-driven portable angle grinder; and formed by         electromechanical or solid state electronic structures for         turning the motor on or off, and/or changing the rotational         speed and/or varying the speed;     -   Control circuit (1300): Provide operational capability for the         execution of turning the commutator-type drive motor (150) on         and off and/or changing the rotational speed and/or varying the         speed; and/or for the control and protection of voltage and         current;     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (152) to provide rotary drive operation for         grinding, polishing and cutting workpieces;     -   Blade (900): Installed between the grinding wheel (800) and the         housing of the commutator-type drive motor (150) in order to         facilitate heat dissipation;     -   Guard (1100): installed on one side of the grinding wheel (800)         and the motor rotating part (152) adjacent to the handle.

The features of the guard lie in its combination with the static part of the commutator-type drive motor (150) through the housing (400), and to serve as another bearing side support of the spindle (300) that drives the internal rotation type motor rotating part (152). Moreover, it allows the interiors of both the commutator-type drive motor (150) and the housing (400) to become an open and interconnecting structure so that the accumulated heat inside a running commutator-type drive motor (150) may flow smoothly between the housing (400) and the motor interior in order to facilitate heat dissipation. In addition, blades (900) are installed on the spindle (300) between the grinding wheel (800) and the housing exterior of the commutator-type drive motor (150) to move air flow outwardly for better motor heat dissipation.

FIG. 11 is second operational diagram of the commutator-type motor formed together by the housing and the internal rotation type motor of the present invention;

The main components are the following:

-   -   Commutator-type drive motor (150): Formed by alternating current         or direct current Commutator-type drive motor (150) in flat,         disc or relatively short cylindrical forms including motor         rotating part (152) with static part (151) and commutator (153),         and brush assembly (154); wherein the static part (151) is         directly installed on the housing (400); the other externally         exposed end of the spindle (300) of the internal rotation type         motor rotating part (152) is provided for the coaxial         installation of the grinding wheel (800) or the circular saw for         workpiece polishing, grinding and cutting operations of the         grinding wheel (800) or the circular saw which are driven by the         internal rotation type motor rotating part (152);     -   Housing (400): A structure formed by solid state material for         the installation of the commutator-type drive motor (150) and a         handle (500) formed by an extended body or assembly. The static         part (151) of the commutator-type drive motor (150) combines         with the housing (400). The deflection angle between the axis of         the spindle (300) of the rotating part (152) of the         commutator-type drive motor (150), and the axis of the handle         (500) is between 30°-150°;     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct commutator-type drive motor         (150)-driven portable angle grinder;     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct commutator-type         drive motor (150)-driven portable angle grinder; and formed by         electromechanical or solid state electronic structures for         turning the motor on or off, and/or changing the rotational         speed and/or varying the speed;     -   Control circuit (1300): Provide operational capability for the         execution of turning the commutator-type drive motor (150) on         and off and/or changing the rotational speed and/or varying the         speed; and/or for the control and protection of voltage and         current;     -   Grinding wheel (800): Installed on the spindle (300) of the         motor rotating part (152) to provide rotary drive operation for         grinding, polishing and cutting workpieces;     -   Blade (900): Installed between the grinding wheel (800) and the         housing of the commutator-type drive motor (150) in order to         facilitate heat dissipation;     -   Guard (1100): installed on one side of the grinding wheel (800)         and the motor rotating part (152) adjacent to the handle;

Its features lie in its combination with the static part of the commutator-type drive motor (150) through the housing (400), and the installation of blades (900) on the spindle (300) between the grinding wheel (800) and the housing exterior of the commutator-type drive motor (150) to move air flow outwardly for better motor heat dissipation.

Furthermore, vents (250) are installed on the housing of the commutator-type drive motor (150) inside the housing (400) of the aforementioned commutator-type drive motor (150) in FIG. 11 in order to facilitate interflow of the accumulated heat of the commutator-type drive motor (150) in the housing (400) space; and from the housing (400), heat is then dissipated outside.

Furthermore, the present invention is formed by internal rotation type flat, disc or relatively short cylindrical alternating current or direct current synchronous or asynchronous brushless motors. The internal rotation type flat, disc or relatively short cylindrical electric motors are for reducing workspace disruption, and to give the drive motor a better heat dissipation environment;

FIG. 12 is the first operational diagram of the structure formed together by the housing and the internal rotation type brushless motor of the present invention;

Its structural mode is the following:

-   -   Brushless motor (160): Formed by alternating current or direct         current brushless motor in flat, disc or relatively short         cylindrical forms including static part (161) and motor rotating         part (162); wherein the static part (161) and the spindle (300)         of the motor rotating part (162) and one end of the bearing are         directly installed on the housing (400); the other externally         exposed end of the spindle (300) of the rotating part (152) of         the internal rotation type brushless motor is for coaxial         installation of the grinding wheel (800) or the circular saw for         workpiece polishing, grinding and cutting operations of the         grinding wheel (800) or the circular saw which are driven by the         internal rotation type motor rotating part (162);     -   Housing (400): A structure formed by solid state material for         the installation of the brushless motor (160) and a handle (500)         formed by an extended body or assembly. The static part (161)         and the spindle (300) of the rotating part (162) of the         brushless motor (160) and one end of the bearing combine with         the housing (400). The deflection angle between the axis of the         spindle (300) of the rotating part (162) of the brushless motor         (160), and the axis of the handle (500) is between 30°-150°;     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct brushless motor (160)-driven         portable angle grinder;     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct brushless motor         (160)-driven portable angle grinder; and formed by         electromechanical or solid state electronic structures for         turning the motor on or off, and/or changing the rotational         speed and/or varying the speed;     -   Control circuit (1300): Provide operational capability for the         execution of turning the brushless motor (160) on and off and/or         changing the rotational speed and/or varying the speed; and/or         for the control and protection of voltage and current;     -   Grinding wheel (800): Installed on the spindle (300) of the         rotating part (162) of the brushless motor (160) to provide         rotary drive operation for grinding, polishing and cutting         workpieces;     -   Blade (900): Installed between the grinding wheel (800) and the         housing of the brushless motor (160) in order to facilitate heat         dissipation;     -   Guard (1100): installed on one side of the grinding wheel (800)         and the motor rotating part (162) adjacent to the handle.

The features of the guard lie in its combination with the static part of the brushless motor (160) through the housing (400), and to serve as another bearing side support of the spindle (300) that drives rotating part (162) of the internal rotation type brushless motor. Moreover, it allows the interiors of both the brushless motor (160) and the housing (400) to become an open and interconnecting structure so that the accumulated heat inside a running brushless motor (160) may flow smoothly between the housing (400) and the motor interior in order to facilitate heat dissipation. In addition, blades (900) are installed on the spindle (300) between the grinding wheel (800) and the housing exterior of the brushless motor (160) to move air flow outwardly for better motor heat dissipation.

FIG. 13 is the second operational diagram of the structure formed together by the housing and the internal rotation type brushless motor;

Its structural mode is the following:

-   -   Brushless motor (160): Formed by alternating current or direct         current brushless motor in flat, disc or relatively short         cylindrical forms including static part (161) and motor rotating         part (162); wherein the static part (161) is directly installed         on the housing (400); the externally exposed end of the spindle         (300) of the rotating part (162) of the internal rotation type         brushless motor (160) is provided for the coaxial installation         of the grinding wheel (800) or the circular saw for workpiece         polishing, grinding and cutting operations of the grinding wheel         (800) or the circular saw which are driven by the internal         rotation type motor rotating part (162);     -   Housing (400): A structure formed by solid state material for         the installation of the brushless motor (160) and a handle (500)         formed by an extended body or assembly. The static part (161) of         the brushless motor (160) combines with the housing (400). The         deflection angle between the axis of the spindle (300) of the         rotating part (162) of the brushless motor (160), and the axis         of the handle (500) is between 30°-150°;     -   Handle (500): A hollow body for the installation of one or more         of the following circuit devices including power cord (1500),         manually operated electromechanical device (1400), power storing         and discharging device (1200) and optional devices like control         circuit (1300), or indicator lamp, and display devices for the         operational control of the direct brushless motor (160)-driven         portable angle grinder;     -   Manually operated electromechanical device (1400): An interface         that directly or by way of the control circuit (1300) provide         the operator with the control over the direct brushless motor         (160)-driven portable angle grinder; and formed by         electromechanical or solid state electronic structures for         turning the motor on or off, and/or changing the rotational         speed and/or varying the speed;     -   Control circuit (1300): Provide operational capability for the         execution of turning the brushless motor (160) on and off and/or         changing the rotational speed and/or varying the speed; and/or         for the control and protection of voltage and current;     -   Grinding wheel (800): Installed on the spindle (300) of the         rotating part (162) of the brushless motor (160) to provide         rotary drive operation for grinding, polishing and cutting         workpieces;     -   Blade (900): Installed between the grinding wheel (800) and the         housing of the brushless motor (160) in order to facilitate heat         dissipation;     -   Guard (1100): installed on one side of the grinding wheel (800)         and the motor rotating part (162) adjacent to the handle.

Its features lie in its combination with the static part of the brushless motor (160) through the housing (400), and the installation of blades (900) on the spindle (300) between the grinding wheel (800) and the housing exterior of the brushless motor (160) to move air flow outwardly for better motor heat dissipation.

Furthermore, vents (250) are installed on the housing of the brushless motor (160) inside the housing (400) of the aforementioned brushless motor (160) in FIG. 13 in order to facilitate interflow of the accumulated heat of the brushless motor (160) in the housing (400) space; and from the housing (400), heat is then dissipated outside. 

What is claimed is:
 1. A direct motor-driven angle grinder, comprising: a drive motor having an inner housing part, a rotating outer housing part that encloses a rotating part of the motor and surrounds the inner housing part, and a spindle connected to the rotating outer housing part; a handle fixed to an extending from the inner housing part, wherein an angle between an axis of the handle and an axis of the housing is between 30° and 150°; and a grinding wheel or a circular saw fixed to the spindle so as to rotate with the rotating outer housing and be directly driven by the drive motor, wherein the rotating outer housing part of the drive motor serves as a flywheel during operation of the motor to rotate the grinding wheel or circular saw.
 2. A direct motor-driven angle grinder as claimed in claim 1, further comprising a guard installed on one side of the grinding wheel or the circular saw and the rotating outer housing part, and adjacent to the handle.
 3. A direct motor-driven angle grinder as claimed in claim 1, wherein a manually operated electro-mechanical control device is arranged to carry out one or more of the following control functions: turn the motor on and off and control a rotational speed of the motor.
 4. A direct motor-driven angle grinder as claimed in claim 1, wherein a rotor of the motor is snugly installed within the rotating outer housing part of the motor.
 5. A direct motor-driven angle grinder as claimed in claim 1, wherein the inner housing part supports a stator winding.
 6. A direct motor-driven angle grinder as claimed in claim 1, wherein a rotor of the motor is integrated with the rotating outer housing part of the motor.
 7. A direct motor-driven angle grinder as claimed in claim 1, wherein the rotating outer housing part has a high inertial mass.
 8. A direct motor-driven angle grinder as claimed in claim 1, wherein the rotating outer housing part is integrated with a high inertial mass body.
 9. A direct motor-driven angle grinder as claimed in claim 1, wherein the handle is a hollow body.
 10. A direct motor-driven angle grinder as claimed in claim 9, wherein the handle contains a manually-operated electromechanical control device for the drive motor and a power storing and discharging device for supplying power to the drive motor through a power cable to cause the spindle to rotate.
 11. A direct motor-driven angle grinder as claimed in claim 10, wherein the handle further contains a control circuit for performing one or more motor control functions including turning the motor on and off, changing a rotational speed, or control and protection of voltage and current.
 12. A direct motor-driven angle grinder as claimed in claim 11, wherein the motor control functions include at least one of the following functions: turning the motor on and off, changing or varying a rotational speed, and control and protection of voltage and current.
 13. A direct motor-driven angle grinder as claimed in claim 10, wherein the manually operated electromechanical device is an interface that directly or by way of a control circuit provides an operator with control over the direct motor-drive portable angle grinder; said electromechanical device being arranged to enable the operator to turn the motor on and off, and/or change or vary a speed.
 14. A direct motor-driven angle grinder as claimed in claim 1, wherein power to the drive motor is supplied by a power cord connected to an external power source.
 15. A direct motor-driven angle grinder as claimed in claim 1, wherein a power source includes a power storing and discharging device. 